Magnesium Sulfate

Mechanism :

MgSO4 is a CNS depressant, blocks peripheral neuromuscular transmission, and acts as an anticonvulsant. It decreases the quantity of acetylcholine released at the motor end plate.

MgSO4 also depresses the myocardium and prolongs conduction time,

It promotes the movement of calcium, potassium, and sodium in and out of cells and stabilizes cell membranes.

It promotes osmotic retention of fluid in the colon and causes distention and increased peristalsis which aids in bowel evacuation.

Indication :

Acute nephritis
Hypomagnesemia
Bronchospasm (Off-label)
Toxemias of Pregnancy

Contraindications :

• Contraindicated in hypersensitivity to drug components

• Contraindicated in myocardial damage and heart block

• Contraindicated in diabetic coma

• Contraindicated in hypermagnesemia

• Contraindicated in hypercalcemia

• Use cautiously in patients with renal impairment

• Use cautiously in patients with myasthenia gravis

• Use cautiously in patients with neuromuscular disorder

Dosing :

Injectable solution: 40 mg/ml, 80 mg/ml, 50%

Infusion solution: 1 g/100ml, 2 g/100ml

Acute Nephritis:

100 mg/kg intramuscularly every 4-6 hourly PRN OR 20-40 mg/kg intramuscularly PRN

Severe nephritis: 100/200 mg/kg intravenously as 1-3% solution; total dose to be given within 1 hour, one half within 15-20 minutes.

Hypomagnesemia:

25-50 mg/kg every 4-6 hourly for 3-4 dosed PRN OR 100-200 mg/kg every 6 hourly orally

Bronchospasm:

25-50 mg/kg intravenously over 10-20 minutes.

Adverse Effect :

Flushing, sweating, hypocalcemia, vision changes, hyperkalemia, hypophosphatemia, cardiac depression, hypotension, hypothermia, circulatory collapse, pulmonary edema, respiratory paralysis, depressed reflexes, drowsiness.

Lactation :

Safe during lactation

Hepatic Dose :

No dose adjustments needed

Pregnanacy :

Pregnancy category D